TW201309520A - Brake lining for railway vehicles and disc brakes equipped with same - Google Patents

Abstract

The disc brake for railway vehicles is equipped with a brake disc that is fixed to the wheel or axle of a railway vehicle and a brake lining that is pressed against the sliding surface of the brake disc by brake calipers. The brake lining is obtained from: multiple friction members, the respective surfaces of which face the sliding surface of the brake disc, each friction member being disposed with gaps therebetween; back metals secured to the back surfaces of every friction member; and a substrate, which supports every friction member from the back surface via a spring member and which is installed on the brake calipers. With two adjacent friction members as a set, the back metal of the set of friction members is a single piece. Disc brakes of said configuration achieve both homogenization of contact surface pressure between the brake lining and the brake disc during braking and stabilization of the coefficient of friction therebetween as well as improving durability and reliability.

Description

Brake lining for railway vehicles and disc brakes therewith

The present invention relates to a disc brake used as a brake device for a railway vehicle, and more particularly to a brake lining for a railway vehicle that is pressed to a sliding surface of a brake disc fixed to a wheel or an axle, and a railway provided therewith Disc brakes for vehicles.

In recent years, brake devices for railway vehicles, land vehicles, and automobiles, such as automobiles and locomotives, have been equipped with disc brakes in response to the increase in speed and size of vehicles. The disc brake is a brake force device obtained by the friction generated by the sliding of the brake disc and the brake lining.

In the case of a disc brake for a railway vehicle, a donut-shaped disc-shaped brake disc is attached to a wheel or an axle, and a brake lining is pressed against a sliding surface of the brake disc by a brake caliper to generate a braking force. Thereby, the rotation of the wheel or the axle is braked to control the speed of the vehicle.

At this time, the deceleration speed of the vehicle is dependent on the braking force of the disc brake, and the braking force is greatly dependent on the friction coefficient between the brake disc and the brake lining. In actual walking, it is desirable to be able to surely control the deceleration speed of the vehicle during braking. Therefore, even if the traveling speed at the start of braking is different, the friction coefficient between the brake disc and the brake lining can be stably maintained.

In the braking process, the brake lining and the sliding surface of the brake disc that are in contact with each other rise due to the frictional heat temperature. This temperature rise is a condition in which the brake load becomes large, and specifically, the traveling speed of the vehicle is a high speed condition. There is a tendency to become more pronounced when the vehicle is heavy. In actual walking, it is desirable to prevent thermal damage of the disc brake and improve durability. Therefore, it is necessary to make the contact between the brake lining and the brake disc during braking as uniform as possible, and to reduce the occurrence of frictional heat.

Fig. 1 is a view showing a conventional disc brake for a railway vehicle. Fig. 1(a) is a plan view showing a brake lining, and Fig. 1(b) is a cross-sectional view showing AA of Fig. 1(a). Enlarged image. In Fig. 1(a), the state in which the brake lining is seen from the brake disc side on the surface side is shown.

A conventional brake lining (hereinafter referred to as "a conventional brake lining") 102 shown in Fig. 1 is composed of a plurality of plate-shaped friction members 103 having a wide width and a plurality of friction members 103. The metal spacer 104 fixed on the back surface and the substrate 106 holding the respective friction members 103 from the back side together with the metal spacer 104 are formed. Each of the friction members 103 is strongly attached to the substrate 106 by a rivet (not shown) together with the metal spacer 104. The conventional brake lining 102 of such a configuration is in a state in which the brake caliper mounting substrate 106 (not shown) faces the sliding surface 101a of the brake disc 101 with the surface of each friction member 103.

The brake caliper actuates the hydraulic pressure and the air pressure as a driving source during braking, and presses the brake lining 102 against the brake disc 101. At this time, the pressure applied from the brake caliper to the brake lining 102 does not uniformly act on the entire area of the brake lining 102 due to the structure of the mounting portions of the two, but concentrates on a specific portion.

Therefore, in the case of using the disc brake of the conventional brake lining 102, since the friction member 103 is formed into a plate shape to a certain extent, it is strongly fixed to the base. The plate 106 is so that the contact pressure of the brake disc 101 and the brake lining 102 is locally increased during braking. As a result, the temperature rise caused by the friction in the brake is locally excessive, and thus the excessive temperature rise causes the brake lining 102 (friction member 103) and the brake disc 101 to be worn up, and the brake is applied. The disc 101 will crack. Because of this thermal damage, the durability of the disc brakes is degraded.

In order to solve such a problem, in recent years, it has been aimed at uniformizing the contact surface pressure of the brake lining and the brake disc during braking, and brake linings of various improved structures have been proposed. For example, Patent Literatures 1 to 3 describe a brake lining in which a friction member of a conventional brake lining is divided into small sizes and the divided plurality of friction members are arranged with a gap therebetween.

In the brake lining disclosed in Patent Document 1, a metal gasket is fixed to each of the back surfaces of the friction members. Each of the friction members is elastically supported by being attached to the substrate by rivets from the back side through the spring members, respectively.

In the brake lining disclosed in the above-mentioned Patent Document 2, two friction members adjacent to each other are grouped, and an elastic sheet integrally formed is fixed across the back surface of the friction members of the group. Each of the elastic pieces is a portion corresponding to a gap between the friction members fixed to the elastic piece, and is strongly attached to the substrate by two rivets, whereby each of the friction members is between the friction members The rivet positions at the two places are elastically supported as fulcrums.

In the brake lining disclosed in the aforementioned Patent Document 3, two friction members adjacent to each other are grouped as one set, and the integrally formed thin metal layer is spanned. Both of them are fixed to the back of the friction member of this group. Each of the thin metal layers corresponds to a portion that is fixed to the gap between the friction members of the metal thin layer. However, the elastic elastic element is attached to the substrate by two rivets, whereby the friction members are The rivet positions at two places of the friction members are elastically supported as fulcrums.

Since the brake lining disclosed in the above Patent Documents 1 to 3 is such that the friction member is elastically supported on the substrate, uniformity of the brake disk and the contact surface pressure can be expected during braking.

However, in the brake lining disclosed in Patent Document 1, since the friction members can be independently operated, the friction coefficient between the brake disc and the brake lining may vary depending on the traveling speed at the start of braking. The brake lining disclosed in the above-mentioned Patent Documents 2 and 3 also occurs in the variation of the friction coefficient. Since each of the friction members is a pair of friction members as a fulcrum and is elastically supported by the elastic sheets or the thin metal layers, the friction members are independently movable and are not changed.

When the friction coefficient changes depending on the traveling speed at the start of braking, it is difficult to reliably control the deceleration speed of the vehicle during braking, and the required brake performance cannot be ensured. In particular, in the case of a high-speed railway vehicle such as a Shinkansen, since the traveling speed is a wide range from a low speed to a high speed, the variation of the friction coefficient is regarded as a problem.

Further, in the case of the brake lining of Patent Document 1, since each of the friction members is coupled to the substrate by one rivet, it rotates in place during braking. With the repeated braking, if the rotation of the friction member is reversed, the joint between the friction member and the substrate will be loosened, eventually leading to the friction member. Lost. Therefore, sufficient durability and reliability cannot be ensured.

[Advanced technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2008-151188

[Patent Document 2] International Publication WO2002/073059

[Patent Document 3] Japanese Laid-Open Patent Publication No. 2006-194429

The present invention has been made in view of the above problems, and an object thereof is to provide a brake lining and a disc brake for a railway vehicle, which can be two-folded: uniformity of contact surface pressure of a brake lining and a brake disc during braking, and friction between those The coefficient is stabilized and durability and reliability are improved.

In order to achieve the above object, the inventors of the present invention carried out various tests and analyses and focused on the results of the review, and obtained the following (a) to (c).

(a) As described above, in the uniformization of the contact surface pressure of the brake lining and the brake disc during braking, it is necessary to elastically support a plurality of small-sized friction members, respectively, so that the friction members are respectively movable. However, in order to stabilize the friction coefficient between the brake disc and the brake lining, it is necessary to make the operation of each friction member a certain degree of restraint.

(b) The uniformity of the contact surface pressure and the stabilization of the friction coefficient shown in the above (a), as long as the two friction members adjacent to each other are connected As a group, the back surface of the friction member of the group is fixed across the metal gasket integrally formed by the two, and the friction members are respectively mounted on the substrate by the rivet from the back side through the spring member. Standing. Since each of the friction members is attached to the substrate by the rivets through the spring members, the friction members can be moved separately. Further, by integrally fixing the metal shim on the back surface of the friction members of one set, the friction members of one set are connected by the metal shim, and the operation thereof needs to be minimally restrained.

(c), in the case of the structure shown in the above (b), since the friction members are substantially joined by the two rivets to the substrate, they do not rotate in place during braking, and the friction members and the substrate can be prevented. The joint portion is loosened, and even if the joint portion at one location is broken, the friction member is not immediately lost.

The present invention has been completed in accordance with the techniques shown in the above (a) to (c), and is basically the brake lining for a railway vehicle shown in the following (I) and the railway vehicle shown in the following (II). Disc brakes.

(I) A brake lining for a railway vehicle, which is a brake lining that is fixed to a sliding surface of a brake disc of a wheel or axle of a railway vehicle, and is pressed by a brake caliper, characterized in that: each surface is respectively a plurality of friction members that face each other with a sliding surface of the brake disc facing each other with a gap therebetween, and a metal spacer that is fixed to the back surface of each friction member, and a spring member that passes each of the friction members from the back side through the center portion The base plate is supported and mounted on the brake caliper, and two friction members adjacent to each other are grouped as one set, and the metal spacers of the friction members of the set are integrally formed.

For the brake lining of the above (I), the aforementioned metal gasket is equivalent to The portion that is fixed to the gap between the friction members of the metal spacer is preferably formed into a neck portion. In this case, the minimum width of the neck of the metal gasket is preferably 1/3 to 2/3 of the maximum width of the friction member fixed to the metal gasket.

Further, in the brake lining of the above (I), the metal gasket is preferably a minimum length of a portion corresponding to a gap between the friction members fixed to the metal gasket of 2 to 7 mm.

(II) A disc brake for a railway vehicle, comprising: a brake disc fixed to a wheel or an axle of a railway vehicle; and a brake caliper to which the brake lining of any of the above is attached.

According to the brake lining and the disc brake of the railway vehicle according to the present invention, by the two friction members adjacent to each other as a group, the back surface of the friction member of the group is integrated with the metal formed integrally therewith. When the spacers are fixed and the friction members are respectively mounted on the substrate by the rivets from the back side, the contact surface pressure of the brake lining and the brake disc during braking is uniform, and the friction coefficient between them is stabilized. It can be set up and can improve durability and reliability.

Hereinafter, an embodiment of the brake lining and the disc brake for a railway vehicle according to the present invention will be described in detail.

Fig. 2 is a view showing an example of a disc brake for a railway vehicle according to the present invention. Fig. 2(a) is a plan view showing a brake lining, Fig. 2(b) is an enlarged plan view showing a pair of friction members, and Fig. 2(c) is an enlarged view showing a BB section of Fig. 2(a). Figure. In the second drawings (a) and (b), the state in which each of the brake linings and the set of friction members is seen from the side of the brake disc on the front side is shown.

As shown in Fig. 2(c), the disc brake of the present invention includes a brake disc 1, a brake lining 2, and a brake caliper (not shown) to which the brake lining 2 is attached. The brake disk 1 is a donut-shaped disk shape, and is attached to a wheel or an axle (not shown) by bolts or the like, and is strongly fixed. The brake caliper is actuated during braking to press the brake lining 2 against the sliding surface 1a of the brake disc 1. As a result, friction generated by the sliding between the brake disc 1 and the brake lining 2 causes the braking force to occur. In this case, the disc brake is to brake the rotation of the wheel or the axle to control the speed of the vehicle.

The brake lining 2 of the present invention shown in Fig. 2 is composed of a plurality of friction members 3, a metal spacer 4, a spring member 5, and a substrate 6 that holds all of these. The friction member 3 has surfaces that face the sliding surface 1a of the brake disc 1 and are spaced apart from each other with a gap therebetween. For example, as shown in Fig. 2(a), the friction member 3 may be arranged in two in the radial direction of the brake disk 1, and four in total in the circumferential direction of the brake disk 1. The arrangement and the number of the friction members 3 are not particularly limited.

The friction member 3 is made of a copper sintered material, a resin material, or the like, and the plate-shaped friction member 103 having a wide width in the conventional brake lining 102 shown in Fig. 1 is divided into small pieces. . Friction member 3, is As shown in Fig. 2 (a) and (b), the planar shape is circular, and has a small hole 3a at the center portion thereof. In this small hole 3a, the rivet 7 is inserted when the friction member 3 is mounted on the substrate 6. The planar shape of the friction member 3 is not limited to a circular shape, and a polygonal shape such as a square shape or a hexagonal shape may be used.

In order to maintain the strength and rigidity of the back surface of each of the friction members 3, a metal spacer 4 made of a thin metal plate such as steel is fixed. The metal shim 4 is formed by integrally forming two friction members 3 adjacent to each other as one of the friction members 3 that are adjacent to each other. Thereby, the friction member 3 of one set is connected by the metal spacer 4. The friction members 3 of a group connected by the metal spacers 4 are not limited to the adjacent directions, are adjacent to each other in the radial direction of the brake disk 1, are adjacent to each other in the circumferential direction, and are adjacent to each other in directions other than those. can.

Each of the friction members 3 is attached to the substrate 6 by rivets 7 that are inserted into the small holes 3a of the respective center portions together with the metal spacers 4. Here, in each of the friction members 3, the spring members 5 are disposed between the metal spacers 4 on the back side and the substrate 6, and are respectively elastically supported. Further, although the spring member 5 is a disk spring in the second drawing, a leaf spring and a coil spring may be used.

According to the disc brake of the brake lining 2 having such a configuration, each of the friction members 3 is attached to the substrate 6 via the rivet 7 through the spring member 5, whereby the respective friction members 3 are elastically supported, so that they can be separately operated. . Therefore, the contact surface pressure of the brake lining 2 and the brake disc 1 during braking can be uniformized.

And one of the friction members 3 of the set is fixed across the back of the friction member 3 Since the metal spacers 4 formed by the body are in a state in which the friction members 3 are connected by the metal spacers 4, the operation is minimized as compared with the case where the metal spacers are not connected. Be restrained. Therefore, the friction coefficient between the brake disc 1 and the brake lining 2 can be stabilized without depending on the traveling speed at the start of braking.

Further, since each of the friction members 3 is substantially coupled to the substrate 6 by the two rivets 7, it does not rotate in place during braking, and the loosening of the joint portion with the substrate 6 can be prevented. It is assumed that even in the case where the joint portion is loose, as long as the joint portions at the two places are not simultaneously broken, the friction member 3 is not immediately lost. Therefore, it is possible to ensure sufficient durability and reliability of the disc brake.

However, since each of the friction members 3 is elastically supported by the position of the rivet 7 directly below the center portion as a fulcrum, even if it is movable while being in contact with the brake disk 1 during braking, it does not greatly tilt, and the contact surface can be horizontally Uniform wear across the whole world without partial wear.

In the brake lining 2 of the present invention, as shown in Figs. 2(a) and (b), the metal spacer 4 corresponds to the portion 4a of the gap between the friction members 3 fixed to each other. That is, it is preferable that the joint portion 4a of the friction members 3 is formed into a neck portion. It is advantageous because the point of weight reduction can be achieved. In this case, the metal spacer 4 is the minimum width w of the connecting portion 4a (neck), which is 1/3 to 2/3 of the maximum amplitude D of the friction member 3 fixed thereto, and the thickness t (Fig. 2) (c) Reference) is preferably 1.5 to 4 mm. This makes it possible to effectively achieve the above-described uniformity of the contact area and stabilization of the friction coefficient. Moreover, the maximum amplitude D of the friction member 3 herein refers to the joint portion. The maximum width of the friction member 3 in the direction in which the minimum width w of the points 4a is parallel.

Further, in the brake lining 2 of the present invention, as shown in FIGS. 2(a) and (b), the metal spacer 4 is the minimum length 1 of the joint portion 4a, that is, the minimum gap 1 between the friction members 3 is 2 to 7 mm. Preferably, it is preferably 3 to 5 mm. When the minimum length 1 of the connecting portion 4a is too short, the operation of the friction member 3 is excessively restrained, and the uniformity of the above-described contact area becomes difficult. On the other hand, if it is too long, the operation of the friction member 3 cannot be sufficiently restrained, and stabilization of the above-described friction coefficient becomes difficult.

Further, the spring constant of the spring member 5 which is elastically supported by the friction member 3 is preferably 4 to 10 kN/mm.

[Examples]

In order to confirm the effect of the present invention, the following FEM analysis (finite element method analysis) and brake test were carried out.

[Summary of Analysis and Test]

In order to evaluate the uniformity of the contact surface pressure of the brake lining and the brake disc during braking, FEM analysis was performed. In the analysis, the brake lining and the brake disc are modeled by an elastic body, and a load corresponding to the pressure generated by the brake caliper is given from the back surface of the brake lining. The load acting on each of the friction members at this time was evaluated.

The brake test is performed in order to stabilize the friction coefficient between the brake disc and the brake lining in the brake. In the test, the wheel on which the brake disc is mounted is rotated in place, and the brake lining attached to the brake caliper is pressed against The brake disc is braked. At this time, the friction coefficient is obtained from the pressing load acting on the brake lining and the measured brake torque.

Any of the FEM analysis and the brake test are aimed at the disc brakes used in the Shinkansen.

[Implementation conditions]

The main implementation conditions of the FEM analysis and the brake test are shown in Table 1 below.

In the FEM analysis, the three conditions of the inventive examples 1 to 3 were analyzed using the disc brake shown in Fig. 2 described above. In either case, the thickness of the metal gasket is 2.3 mm, and the minimum width of the joint portion of the metal gasket connecting the friction members of the group is 21 mm. The minimum length of the joint portion of the metal gasket that connects the friction members of one set is changed to 2 mm in the present invention, changed to 3 mm in the present invention example 2, and changed to 5 mm in the present invention example 3.

And in common with the inventive examples 1 to 3, the length direction of the substrate (phase The length in the circumferential direction of the brake disk is 400 mm, and the length in the width direction (corresponding to the length in the radial direction of the brake disk) is 130 mm. The material of each member constituting the brake lining is a copper sintered material, and all of them are iron steel materials. There are 14 friction members whose planar shape is a circle having a diameter of 45 mm. The spring constant of the disc spring disposed between the friction member and the substrate is 7 kN/mm. The brake disc has a substantially disk shape of an inner diameter of 476 mm and an outer diameter of 724 mm, and the length of the sliding surface in contact with the brake lining is 120 mm.

And the FEM analysis is carried out at a pressure of 14 kN, and the friction coefficient of the contact faces of the brake disc and the brake lining is 0.3.

Further, in the FEM analysis, for the comparison, the two conditions of Comparative Examples 1 and 2 were analyzed. In Comparative Example 1, among the conditions of the first embodiment of the present invention, a disc brake that does not have a pair of friction members connected by a metal spacer and individually fixes a metal spacer on the back surface of each friction member (as described above) Patent Document 1), in Comparative Example 2, the conventional disc brake shown in Fig. 1 described above is used.

On the other hand, in the brake test, tests were conducted on the above two conditions of the inventive example 1 and the comparative example 1. For each test, the initial speed is from 8 to 330 km/h, and different speeds of 8 types are selected, and the brakes are stopped at each initial speed.

[Evaluation method]

The object of the present invention is to achieve uniformity of the above-mentioned contact area and stabilization of the friction coefficient, and further ensure the durability of the disc brake. On the brake In the test, in order to evaluate the stabilization and durability of the friction coefficient, the variability of the friction coefficient was investigated for each index, and it was investigated whether or not each of the friction members was rotated in situ. Here, in the average friction coefficient obtained from the brake test of each initial velocity, the maximum value and the minimum value are extracted, and the difference is used as the friction coefficient variability.

On the other hand, in the FEM analysis, in order to evaluate the uniformity of the contact area, the variability of the load acting on each of the friction members was investigated in accordance with the index. Here, in the load acting on each friction member when the pressure is applied, the maximum value and the minimum value are extracted, and the difference is taken as the variability of the load.

[result]

The results of the FEM analysis and the brake test were arranged as shown in Table 2 below.

As is apparent from the results shown in the same table, in the first example of the present invention, since the friction members of one set are connected by the metal spacer, the variability of the friction coefficient is small, and the rotation of the friction member does not occur. Moreover, according to the effect of the elastic support of the friction member produced by the disc spring, in the present invention examples 1 to 3 In the middle, the variability of the load becomes small. As apparent from the above, the disc brake provided with the brake lining of the present invention can stabilize the two contact areas and stabilize the friction coefficient, and further ensure durability.

On the other hand, in Comparative Example 1, since the friction members of one set were not connected by the metal spacer, the variability of the friction coefficient was relatively large, and the plurality of friction members were rotated. Further, in Comparative Example 2, since the conventional brake lining is used, the variability of the load is large.

[Industrial availability]

The brake lining and the disc brake for the railway vehicle of the present invention can be effectively utilized in any railway vehicle, and is also useful for a wide range of high speed railway vehicles in which the traveling speed is from low speed to high speed.

1‧‧‧ brake disc

1a‧‧‧Sliding surface

2‧‧‧Brake lining

3‧‧‧Friction components

3a‧‧‧Small hole

4‧‧‧Metal gasket

4a‧‧‧Link section

5‧‧‧Spring components

6‧‧‧Substrate

7‧‧‧ Rivets

Fig. 1 is a view showing a conventional disc brake for a railway vehicle. Fig. 1(a) is a plan view showing a brake lining, and Fig. 1(b) is a cross-sectional view showing AA of Fig. 1(a). Enlarged image.

Fig. 2 is a view showing an example of a disc brake for a railway vehicle according to the present invention. Fig. 2(a) is a plan view showing a brake lining, and Fig. 2(b) is an enlarged plan view showing a pair of friction members. 2(c) is an enlarged view showing a BB cross section of Fig. 2(a).

1‧‧‧ brake disc

1a‧‧‧Sliding surface

2‧‧‧Brake lining

3‧‧‧Friction components

3a‧‧‧Small hole

4‧‧‧Metal gasket

4a‧‧‧Link section

5‧‧‧Spring components

6‧‧‧Substrate

7‧‧‧ Rivets

Claims (6)

A brake lining for a railway vehicle is a brake lining that is fixed on a sliding surface of a brake wheel of a wheel or axle of a railway vehicle, and is pressed by a brake caliper, characterized in that: each surface is separately associated with a brake disc a plurality of friction members that face each other with a sliding surface facing each other with a gap therebetween, and a metal gasket that is fixed to the back surface of each friction member, and each of the friction members is supported by a spring member from a back side thereof It is composed of a base plate attached to the brake caliper, and two friction members adjacent to each other are grouped, and the metal spacers of the friction members of the group are integrally formed. A brake lining for a railway vehicle according to claim 1, wherein the metal gasket corresponds to a portion of a gap between the friction members fixed to the metal gasket to form a neck portion. A brake lining for a railway vehicle according to the second aspect of the invention, wherein the minimum width of the neck of the metal gasket is 1/3 to 2/3 of a maximum width of the friction member fixed to the metal gasket. The brake lining for a railway vehicle according to any one of claims 1 to 3, wherein the metal gasket is a minimum length of a portion corresponding to a gap between the friction members fixed to the metal gasket. ~7mm. A disc brake for a railway vehicle, characterized in that: A brake disc that is fixed to a wheel or axle of a railway vehicle, and a brake caliper to which the brake lining of any one of claims 1 to 3 is attached. A disc brake for a railway vehicle, comprising: a brake disc fixed to a wheel or an axle of a railway vehicle; and a brake caliper to which a brake lining according to claim 4 of the patent application is attached.